I can’t drink anymore

i’ve never been a heavy drinker but i drank with friends about a few times a month. i blacked out about two months ago and had a really bad hangover. whenever i thought of the taste of alcohol i would gag and almost throw up and i thought it would go away after the weekend. but ever since then ive tried to take sips of beer and i almost throw up every time. is it a tolerance thing? did i develop some disease? lmk